Does steamworks require any incoming ports?

[robin]

I hope someone from steam staff can chime in here.

https://support.steampowered.com/kb_article.php?ref=8571-GLVN-8711&l=english

The page showing which ports Steam requires access to suggest that there is no need to forward any ports for Steam. Everything is listed as outgoing for Steamworks P2P and voice. Other than streaming, the client also does not require any port forwarding to function fully.

The only reason I see to forward ports for steam is the dedicated server.

So if I am correct, there is no need to forward any ports to maximize Steamwork title connectivity. Can some Steam staff confirm if there are any titles on Steamworks that actual benefit from forwarding ports for incoming traffic?

[Satoru]

Note that Steam has built in 'nat punching' which attempts to aleviate the issues around getting networked clients to talk to eachother.

Depending on the game, it may be beneficial to have port forwarding enabled.

[Kargor]

I don't know about voice, but the Steam DRM doesn't need incoming ports. It wouldn't make any sense if it did, and I never had to forward anything for Steam.

You will need incoming ports if a multiplayer game doesn't actually connect to a real server but to one of the PCs participating in the game -- and if that PCs happens to be yours.

[ReBoot]

Nothing in the Steamworks framework needs incoming ports. But as said by others, it might help. NAT punching is more expensive than direct connections.
I have my PC in the router's DMZ, that solves everything.